Thank you for replying! And don't worry about it at all, I downgraded back to 1.6.3 for now, so waiting a few weeks is no problem at all!
I also noticed another difference in the behavior between 1.6.3 and 1.7.1 when it comes to "Middle Center" anchored & "Left" aligned text. It's possible I misconfigured something in 1.7.1 related to the new options, so I'm not 100% sure if this is a bug or not or me just being stupid. Actually, this might even just be the same thing as the previously mentioned bug (if that's the case, sorry for making a redundant post like this), but I wasn't sure and it seemed different enough to me from the other bug that I thought it might help if I uploaded a video of it. The behavior in 1.6.3 seems more desirable, since it's closer to how Mario and Zelda work.
Video of STM 1.7.1 (Text moves around to be vertically centered as it types out):
Video of STM 1.6.3 (Vertical center is precalculated before it writes out, so text doesn't shift up and down as it types out):